Almaden
Almaden is a town in Spain, about sixty miles north of Cordova. It is noted for its quicksilver mines, which are the oldest and among the largest in the world. The mines have been in continual production since Roman times.The principal mine is directly under the town, and is about one-fifth of a mile below the surface.
The mines are worked day and night in the winter, but are closed during the summer, when the heat makes the fumes rising from the quicksilver too poisonous to breathe. Convict labor was long employed, but now hired men are used.
Almaden is also the name of a neighborhood in the city of San Jose, California. Like its Spanish namesake, California's Almaden had a number of quicksilver mines. They produced mercury, which was used during gold extraction in the California Gold Rush, but all the mines are now disused. As part of the Silicon Valley, the main industry in the neighborhood is now high technology research and development; IBM's Almaden Research Center is located there.